AMINO ACID

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BISMILLAHIR RAHMANIR RAHIM

WELCOME To our

PRESENtaTIOn

A Presentation on AMINO ACID to netish kumar kundu Lecturer,Dept. of pharmacy, MBSTU

ByRasna Sharmin Keya

Jarin Tasnim Itu Group: ApiMehedi HasanSalman Istiak Sabbir Saiful islam

AMINO ACID

• Amino acids are building blocks of proteins.

Proteins are composed of 20 different amino acid.

• Amino acids are organic compounds having an amino group attached to a chain containing an acid group. Amino acid derived from proteins have the amino group on a-carbon that is the carbon atom next to the carboxyl group.

• All 20 amino acids have common structural features

• All amino acids have an amino group (-NH3

+), a carboxylate (-COO-) group and a hydrogen bonded to the same carbon atom (the -carbon)

• They differ from each other in their side chain called R group.

• R groups vary in structure, size and electric charges and influence the solubility of amino acids in water.

STRUCTURAL FEATURES OF AMINO ACIDS

CLASSIFICATION OF AMINO ACIDS

ACCORDING TO PARTS OF OUR BODY REQUIREMENTS, AMINO ACIDS ARE TWO TYPES:-

1)ESSENTIAL AMINO ACID 2)NON-ESSENTIAL AMINO ACID

ESSENTIAL AMINO ACIDS

Essential amino acids – cannot be synthesized by the body. Therefore they must be present in our diet.

THERE ARE 8 TYPES OF ESSENTIAL AMINO ACID.

THEY NEED TO SUPPLIED IN DAILY DIET1. LYSINE2. LEUCINE3. ISOLEUCINE4. METIONINE5. TRYPTOPHAN6. PHENYLALANINE7. THREONINE8. VALINE

NON ESSENTIAL AMINO ACIDS

They are synthesized in our body. Hence they need not to be consumed in the diet.

Alanine Asparagine Aspartate Glutamate Glutamine

Glycine Proline Serine Cysteine tyrosine

On the basis of nature of reaction in solution ,amino acids are three types.

they are :-

1)ACIDIC AMINO ACID 2)BASIC AMINO ACID 3) NEUTRAL AMINO ACID

ACIDIC AMINO ACID

Acidic amino acid contain one amino group and two carboxyl groups. Two amino acids have acidic these are aspartic acid or aspartate (asp) and glutamic acid or glutamate (glu).

BASIC AMINO ACID

Basic amino acid contain two amino groups and one carboxyl group. Here are three amino acids that have basic. These are arginine (arg), lysine (lys), and histidine (his). 

NEUTRAL AMINO ACID

Neutral amino acid:-it contain one amino group and one carboxyl group. For example: alanine, glycine

METHOD OF PREPARATION OF AMINO ACID

1.By strecker method:The strecker amino acid synthesis is an organic reaction used to convert an aldehyde or ketone and a pri-mary amine or ammonia to an α-amino acid using a metal cyanide, acid catalyst, and water.

2.By koop synthesis:-Α- keto acids are treated with ammonia to form the corresponding amine which on catalytic reduction yields an amino acid.

PROPERTIES OF AMINO ACID

Solubility: most of the amino acids are soluble in water and insoluble in organic solvents.

Melting point: melt at higher temperature (above 200 c)

Taste: sweet - glycine, alanine, valine Tasteless – leucine Bitter – arginine, isoleucine

Optical activity: all the amino acids except glycine possess optical isomers due to presence of asymmetric carbon atom.

Glycine

Alanine and all other amino acids have an asymmetric carbon at position 2 (the a-carbon atom). For this reason they all are optically active and exist in D and L forms. Which are non super-imposable mirror images.

CHEMICAL PROPERTIES

A) reactions due to carboxylic group 1)amino acids form salts (-coona) with bases and estres (-COOR)

with alcohols. 2) deacarboxylation : amino acids undergo decarboxylation to

produce amines.

H2n-ch2-cooh + ba(oh)2 ch3-nh2 + baco3 + h2o Glycine methylamine

3) reaction with ammonia : form amides Aspartic acid + NH3 aspargamine

Glutamic acid + nh3 glutamine

REACTIONS DUE TO NH2 GROUP

1 ) Amino groups behave as bases and combine with acids (eg.Hcl) to form salts.

2) reaction with ninhydrin The a-amino acid reactWith ninhydrin to form a Purple, blue or pink colour Complex.

Ninhydrin reaction is used For the quantitative Determination of amino Acids and proteins.

Oxidative demination :the amino acids undergo oxidative deamination to liberate free ammonia.

Transmethylation: Transfer of amino group from an amino acid to a methyal group is called transmethylation

Amino acids as ampholytes : amino acids contain both acidic (-COOH) and basic (-NH2) groups. They can donate a proton and accept a proton. Hence they are also called as ampholytes.

Zwitter ions : amino acids also exist in zwitter ion form. Zwitter ion is a hybrid molecule that contain both positive as well as negative ionic groups. Eg. Leucine

- AT ISOELECTRIC PH - CARRIES NO NET CHARGE

ISOELECTRIC POINT

Isoelectric point:-in acidic solution, an amino acid exist as a positive ion and migrates toward the cathode.In basic solution the amino acid exist as a negative ion and migrates toward the anode. At a certain ph that is hydrogen ion concentration the amino acid molecule would not migrate to either electrode and exist as a a neutral dipolar ion. This ph is called the isoelectric point of amino acid.

ISOELECTRIC POINT OF SOME AMINO ACIDALANIN 6.1VALINE 6.0SERINE 5.7THREONINE 5.6ASPARTIC ACID 2.8GLUTAMIC ACID 3.2 LYSINE 9.7ARGININE 10.8

TRANSAMINATION

Definition:-Transamination as the name implies, refers to the transfer of an amine group from one molecule to another. This reaction is catalyzed by a family of enzymes called transaminases. Actually, the transamination reaction results in the exchange of an amine group on one acid with a keto . New group on another acid.

BIOLOGICAL SIGNIFICANCE OF TRANSAMINATION

• Transamination is used both for the catabolic as well as anabolic processes.

• The resultant α-keto acid can be completely oxidized to provide energy, glucose, fats or ketone bodies depending upon the cellular requirement.

• Since it is a reversible process, it is also used for the synthesis of non essential amino acids.

IMPORTANCE OF AMINO ACIDS

• Amino Acids are the building blocks of proteins• They are important in many biological molecules,

such as forming parts of coenzymes• Or as precursors for the biosynthesis of molecules

such as heme• They are critical to life, and have many functions

in metabolism

THANKS TO ALL